Free Will

The term “free will” has emerged over the past two
millennia as the canonical designator for a significant kind of
control over one’s actions. Questions concerning the
nature and existence of this kind of control (e.g., does it require
and do we have the freedom to do otherwise or the power of
self-determination?), and what its true significance is (is it
necessary for moral responsibility or human dignity?) have been taken
up in every period of Western philosophy and by many of the most
important philosophical figures, such as Plato, Aristotle, Augustine,
Aquinas, Descartes, and Kant. (We cannot undertake here a review of
related discussions in other philosophical traditions. For a start,
the reader may consult Marchal and Wenzel 2017 and Chakrabarti 2017
for overviews of thought on free will, broadly construed, in Chinese
and Indian philosophical traditions, respectively.) In this way, it
should be clear that disputes about free will ineluctably involve
disputes about metaphysics and ethics. In ferreting out the kind of
control involved in free will, we are forced to consider questions
about (among others) causation, laws of nature, time, substance,
ontological reduction vs emergence, the relationship of causal and
reasons-based explanations, the nature of motivation and more
generally of human persons. In assessing the significance of free
will, we are forced to consider questions about (among others)
rightness and wrongness, good and evil, virtue and vice, blame and
praise, reward and punishment, and desert. The topic of free will also
gives rise to purely empirical questions that are beginning to be
explored in the human sciences: do we have it, and to what degree?

Here is an overview of what follows. In Section 1, we
acquaint the reader with some central historical contributions to our
understanding of free will. (As nearly every major and minor figure
had something to say about it, we cannot begin to cover them all.) As
with contributions to many other foundational topics, these ideas are
not of ‘merely historical interest’: present-day
philosophers continue to find themselves drawn back to certain
thinkers as they freshly engage their contemporaries. In Section
2, we map the complex architecture of the contemporary discussion
of the nature of free will by dividing it into five subtopics: its
relation to moral responsibility; the proper analysis of the freedom
to do otherwise; a powerful, recent argument that the freedom to do
otherwise (at least in one important sense) is not necessary
for moral responsibility; ‘compatibilist’ accounts of
sourcehood or self-determination; and ‘incompatibilist’ or
‘libertarian’ accounts of source and
self-determination. In Section 3, we consider arguments from
experience, a priori reflection, and various scientific findings and
theories for and against the thesis that human beings have free will,
along with the related question of whether it is reasonable to believe
that we have it. Finally, in Section 4, we survey the
long-debated questions involving free will that arise in classical
theistic metaphysics.

1. Major Historical Contributions

1.1 Ancient and Medieval Period

One finds scholarly debate on the ‘origin’ of the notion
of free will in Western philosophy. (See, e.g., Dihle (1982) and, in
response Frede (2011), with Dihle finding it in St. Augustine
(354–430 CE) and Frede in the Stoic Epictetus
(c. 55–c. 135 CE)). But this debate presupposes a fairly
particular and highly conceptualized concept of free will, with
Dihle’s later ‘origin’ reflecting his having a yet
more particular concept in view than Frede. If, instead, we look more
generally for philosophical reflection on choice-directed control over
one’s own actions, then we find significant discussion in Plato
and Aristotle (cf. Irwin 1992). Indeed, on this matter, as with so
many other major philosophical issues, Plato and Aristotle give
importantly different emphases that inform much subsequent
thought.

In Book IV of The Republic, Plato posits rational, spirited,
and appetitive aspects to the human soul. The wise person strives for
inner ‘justice’, a condition in which each part of the
soul plays its proper role—reason as the guide, the spirited
nature as the ally of reason, exhorting oneself to do what reason
deems proper, and the passions as subjugated to the determinations of
reason. In the absence of justice, the individual is enslaved to the
passions. Hence, freedom for Plato is a kind of self-mastery, attained
by developing the virtues of wisdom, courage, and temperance,
resulting in one’s liberation from the tyranny of base desires
and acquisition of a more accurate understanding and resolute pursuit
of the Good.

While Aristotle shares with Plato a concern for cultivating virtues,
he gives greater theoretical attention to the role of choice in
initiating individual actions which, over time, result in habits, for
good or ill. In Book III of the Nicomachean Ethics, Aristotle
says that, unlike nonrational agents, we have the power to do or not
to do, and much of what we do is voluntary, such that its origin is
‘in us’ and we are ‘aware of the particular
circumstances of the action’. Furthermore, mature humans make
choices after deliberating about different available means to our
ends, drawing on rational principles of action. Choose consistently
well (poorly), and a virtuous (vicious) character will form over time,
and it is in our power to be either virtuous or vicious.

A question that Aristotle seems to recognize, while not satisfactorily
answering, is whether the choice an individual makes on any given
occasion is wholly determined by his internal state—perception
of his circumstances and his relevant beliefs, desires, and general
character dispositions (wherever on the continuum between virtue and
vice he may be)—and external circumstances. He says that
“the man is the father of his actions as of
children”—that is, a person’s character shapes how
she acts. One might worry that this seems to entail that the person
could not have done otherwise—at the moment of choice, she has
no control over what her present character is—and so she is not
responsible for choosing as she does. Aristotle responds by contending
that her present character is partly a result of previous
choices she made. While this claim is plausible enough, it seems to
‘pass the buck’, since ‘the man is the father’
of those earlier choices and actions, too.

We note just a few contributions of the subsequent centuries of the
Hellenistic era. This period was dominated by debates between
Epicureans, Stoics, and the Academic Skeptics, and as it concerned
freedom of the will, the debate centered on the place of determinism
or of fate in governing human actions and lives. The Stoics and the
Epicureans believed that all ordinary things, human souls included,
are corporeal and governed by natural laws or principles. Stoics
believed that all human choice and behavior was causally determined,
but held that this was compatible with our actions being ‘up to
us’. Chrysippus ably defended this position by contending that
your actions are ‘up to you’ when they come about
‘through you’—when the determining factors of your
action are not external circumstances compelling you to act as you do
but are instead your own choices grounded in your perception of the
options before you. Hence, for moral responsibility, the issue is not
whether one’s choices are determined (they are) but in what
manner they are determined. Epicurus and his followers had a more
mechanistic conception of bodily action than the Stoics. They held
that all things (human soul included) are constituted by atoms, whose
law-governed behavior fixes the behavior of everything made of such
atoms. But they rejected determinism by supposing that atoms, though
law-governed, are susceptible to slight ‘swerves’ or
departures from the usual paths. Epicurus has often been understood as
seeking to ground the freedom of human willings in such
indeterministic swerves, but this is a matter of controversy. If this
understanding of his aim is correct, how he thought that this scheme
might work in detail is not known. (What little we know about his
views in this matter stem chiefly from the account given in his
follower Lucretius’s six-book poem,
On the Nature of Things.)

A final notable figure of this period was Alexander of Aphrodisias,
the most important Peripatetic commentator on Aristotle. In his On
Fate, Alexander sharply criticizes the positions of the
Stoics. He goes on to resolve the ambiguity in Aristotle on the
question of the determining nature of character on individual choices
by maintaining that, given all such shaping factors, it remains open
to the person when she acts freely to do or not to do what she in fact
does. Many scholars see Alexander as the first unambiguously
‘libertarian’ theorist of the will (for more information
about such theories see section 2 below).

Augustine (354–430) is the central bridge between the ancient
and medieval eras of philosophy. His mature thinking about the will
was influenced by his early encounter with late classical Neoplatonist
thought, which is then transformed by the theological views he
embraces in his adult Christian conversion, famously recounted in his
Confessions. In that work and in the earlier On the Free
Choice of the Will, Augustine struggles to draw together into a
coherent whole the doctrines that creaturely misuse of freedom, not
God, is the source of evil in the world and that the human will has
been corrupted through the ‘fall’ from grace of the
earliest human beings, necessitating a salvation that is attained
entirely through the actions of God, even as it requires,
constitutively, an individual’s willed response of faith. The
details of Augustine’s positive account remain a matter of
controversy. He clearly affirms that the will is by its nature a
self-determining power—no powers external to it determine its
choice—and that this feature is the basis of its freedom. But he
does not explicitly rule out the will’s being internally
determined by psychological factors, as Chrysippus held, and Augustine
had theological reasons that might favor (as well as others that would
oppose) the thesis that all things are determined in some manner by
God. Scholars divide on whether Augustine was a libertarian or instead
a kind of compatibilist with respect to metaphysical freedom. It is
clear, however, that Augustine thought that we are powerfully shaped
by wrongly-ordered desires that can make it impossible for us to
wholeheartedly will ends contrary to those desires, for a
sustained period of time. This condition entails an absence of
something more valuable, ‘true freedom’, in which our wills
are aligned with the Good, a freedom that can be attained only by a
transformative operation of divine grace. This latter, psychological
conception of freedom of will clearly echoes Plato’s notion of
the soul’s (possible) inner justice.

Thomas Aquinas (1225–1274) attempted to synthesize major strands
of Aristotle’s systematic philosophy with Christian theology,
and so Aquinas begins his complex discussion of human action and
choice by agreeing with Aristotle that creatures such as ourselves who
are endowed with both intellect and will are hardwired to will certain
general ends ordered to the most general goal of goodness. Will is
rational desire: we cannot move towards that which does not
appear to us at the time to be good. Freedom enters the picture when
we consider various means to these ends and move ourselves to activity
in pursuit of certain of them. Our will is free in that it is not
fixed by nature on any particular means, and they generally do not
appear to us either as unqualifiedly good or as uniquely satisfying
the end we wish to fulfill. Furthermore, what appears to us to be good
can vary widely—even, over time, intra-personally. So much is
consistent with saying that in a given total circumstance (including
one’s present beliefs and desires), one is necessitated to will
as one does. For this reason, some commentators have taken Aquinas to
be a kind of compatibilist concerning freedom and causal or
theological determinism. In his most extended defense of the thesis
that the will is not ‘compelled’ (DM 6), Aquinas
notes three ways that the will might reject an option it sees as
attractive: (i) it finds another option more attractive, (ii) it comes
to think of some circumstance rendering an alternative more favorable
“by some chance circumstance, external or internal”, and
(iii) the person is momentarily disposed to find an alternative
attractive by virtue of a non-innate state that is subject to the will
(e.g., being angry vs being at peace). The first consideration is
clearly consistent with compatibilism. The second at best points to a
kind of contingency that is not grounded in the activity of the will
itself. And one wanting to read Aquinas as a libertarian might worry
that his third consideration just passes the buck: even if we do
sometimes have an ability to directly modify perception-coloring
states such as moods, Aquinas’s account of will as rational
desire seems to indicate that we will do so only if it seems
to us on balance to be good to do so. Those who read Aquinas as a
libertarian point to the following further remark in this text:
“Will itself can interfere with the process [of some
cause’s moving the will] either by refusing to consider what
attracts it to will or by considering its opposite: namely, that there
is a bad side to what is being proposed…” (Reply to 15;
see also DV 24.2). For discussion, see MacDonald (1998); and for
thorough discussion of Aquinas’s theory of action, see Donagan
(1985) and Stump (2003, ch. 9).

John Duns Scotus (1265/66–1308) was the stoutest defender in the
medieval era of a strongly libertarian conception of the will,
maintaining on introspective grounds that will by its very nature is
such that “nothing other than the will is the total cause”
of its activity (QAM). Indeed, he held the unusual view that
not only up to but at the very instant that one is willing
\(X\), it is possible for one to will \(Y\) or at least not to will
\(X\). (He articulates this view through the puzzling claim that a
single instant of time comprises two ‘instants of nature’,
at the first but not the second of which alternative possibilities are
preserved.) In opposition to Aquinas and other medieval Aristotelians,
Scotus maintained that a precondition of our freedom is that there are
two fundamentally distinct ways things can seem good to us: as
practically advantageous to us or as according with justice. Contrary
to some popular accounts, however, Scotus allowed that the scope of
available alternatives for a person will be more or less
constricted. He grants that we are not capable of willing something in
which we see no good whatsoever, nor of positively repudiating
something which appears to us as unqualifiedly good. However, in
accordance with his uncompromising position that nothing can be the
total cause of the will other than itself, he held that where
something does appear to us as unqualifiedly good (perfectly suited
both to our advantage and justice)—viz., in the ‘beatific
vision’ of God in the afterlife—we still can refrain
from willing it.

1.2 Modern Period and Twentieth Century

The problem of free will was an important topic in the modern period,
with all the major figures wading into it (Descartes 1641 [1988], 1644
[1988]; Hobbes 1654 [1999], 1656 [1999]; Spinoza 1677 [1992]; Leibniz
1686 [1991]; Locke 1690 [1975]; Hume 1740 [1978], 1748 [1975]; Edwards
1754 [1957]; Kant 1781 [1998], 1785 [1998], 1788 [2015]; Reid 1788
[1969]), and it continued to be widely discussed among early twentieth
century philosophers (Moore 1912; Hobart 1934; Schlick 1939;
Nowell-Smith 1948, 1954; Campbell 1951; Ayer 1954; Smart 1961). The
centrality of the problem of free will to the various projects of
early modern philosophers can be traced to two widely, though not
universally, shared assumptions. The first is that without belief in
free will, there would be little reason for us to act morally. More
carefully, it was widely assumed that belief in an afterlife in which
a just God rewards and punishes us according to our right or wrong use
of free will was key to motivating us to be moral (Russell 2008,
chs. 16–17). Life before death affords us many examples in which
vice is better rewarded than virtue and so without knowledge of a
final judgment in the afterlife, we would have little reason to pursue
virtue and justice when they depart from self-interest. And without
free will there can be no final judgement.

The second widely shared assumption is that free will seems difficult
to reconcile with what we know about the world. While this assumption
is shared by the majority of early modern philosophers, what
specifically it is about the world that seems to conflict with freedom
differs from philosopher to philosopher. For some, the worry is
primarily theological. How can we make sense of contingency and
freedom in a world determined by a God who must choose the best
possible world to create? For some, the worry was primarily
metaphysical. The principle of sufficient reason—roughly, the
idea that every event must have a reason or cause—was a
cornerstone of Descartes’s, Leibniz’s, and Spinoza’s
metaphysics. How does contingency and freedom fit into such a world?
For some, the worry was primarily scientific. Given that a proper
understanding of the physical world is one in which all physical
objects are governed by deterministic laws of nature, how does
contingency and freedom fit into such a world? Of course, for some,
all three worries were in play in their work (this is true especially
of Descartes and Leibniz).

Despite many disagreements about how best to solve these worries,
there were three claims that were widely, although not universally,
agreed upon. The first was that free will has two aspects: the freedom
to do otherwise and the power of self-determination. The second is
that an adequate account of free will must entail that free agents are
morally responsible agents and/or fit subjects for punishment. Ideas
about moral responsibility were often a yard stick by which analyses
of free will were measured, with critics objecting to an analysis of
free will by arguing that agents who satisfied the analysis would not,
intuitively, be morally responsible for their actions. The third is
that compatibilism—the thesis that free will is compatible with
determinism—is true. (Spinoza, Reid, and Kant are the clear
exceptions to this, though some also see Descartes as an
incompatibilist [Ragland 2006].)

Since a detailed discussion of these philosophers’ accounts of
free will would take us too far afield, we want instead to focus on
isolating a two-step strategy for defending compatibilism that emerges
in the early modern period and continued to exert considerable force
into the early twentieth century (and perhaps is still at work today).
Advocates of this two-step strategy have come to be known as
“classical compatibilists”. The first step was to argue
that the contrary of freedom is not determinism but external
constraint on doing what one wants to do. For example, Hobbes contends
that liberty is “the absence of all the impediments to action
that are not contained in the nature and intrinsical quality of the
agent” (Hobbes 1654 [1999], 38; cf. Hume 1748 [1975] VIII.1;
Edwards 1754 [1957]; Ayer 1954). This idea led many compatibilists,
especially the more empiricist-inclined, to develop desire- or
preference-based analyses of both the freedom to do otherwise and
self-determination. An agent has the freedom to do otherwise than
\(\phi\) just in case if she
preferred or willed to do otherwise, she would have
done otherwise (Hobbes 1654 [1999], 16; Locke 1690 [1975]) II.xx.8;
Hume 1748 [1975] VIII.1; Moore 1912; Ayer 1954). The freedom to do
otherwise does not require that you are able to act contrary to your
strongest motivation but simply that your action be dependent on your
strongest motivation in the sense that had you desired
something else more strongly, then you would have pursued that
alternative end. (We will discuss this analysis in more detail below in
section 2.2.) Similarly, an agent self-determines her \(\phi\)-ing just in
case \(\phi\) is caused by her strongest desires or
preferences at the time of action (Hobbes 1654 [1999]; Locke
1690 [1975]; Edwards 1754 [1957]). (We will discuss this analysis in
more detail below in section 2.4.) Given these analyses, determinism
seems innocuous to freedom.

The second step was to argue that any attempt to analyze free will in
a way that putatively captures a deeper or more robust sense of
freedom leads to intractable conundrums. The most important examples
of this attempt to capture a deeper sense of freedom in the modern
period are Immanuel Kant (1781 [1998], 1785 [1998], 1788 [2015]) and
Thomas Reid (1788 [1969]) and in the early twentieth century
C. A. Campbell (1951). These philosophers argued that the above
compatibilist analyses of the freedom to do otherwise and
self-determination are, at best, insufficient for free will, and, at
worst, incompatible with it. With respect to the classical
compatibilist analysis of the freedom to do otherwise, these critics
argued that the freedom to do otherwise requires not just that an
agent could have acted differently if he had willed
differently, but also that he could have
willed differently. Free will requires more than free action.
With respect to classical compatibilists’ analysis of
self-determination, they argued that self-determination requires that
the agent—rather than his desires, preferences, or any other
mental state—cause his free choices and actions. Reid
explains:

I consider the determination of the will as an effect. This effect
must have a cause which had the power to produce it; and the cause
must be either the person himself, whose will it is, or some other
being…. If the person was the cause of that determination of
his own will, he was free in that action, and it is justly imputed to
him, whether it be good or bad. But, if another being was the cause of
this determination, either producing it immediately, or by means and
instruments under his direction, then the determination is the act and
deed of that being, and is solely imputed to him. (1788 [1969] IV.i,
265)

Classical compatibilists argued that both claims are incoherent.
While it is intelligible to ask whether a man willed to do what he
did, it is incoherent to ask whether a man willed to will what he
did:

For to ask whether a man is at liberty to will either motion or rest,
speaking or silence, which he pleases, is to ask whether a man
can will what he wills, or be pleased with what he
is pleased with? A question which, I think, needs no answer; and they
who make a question of it must suppose one will to determine the acts
of another, and another to determine that, and so on in
infinitum. (Locke 1690 [1975] II.xx.25; cf. Hobbes 1656 [1999],
72)

In response to libertarians’ claim that self-determination
requires that the agent, rather than his motives, cause his actions,
it was objected that this removes the agent from the natural causal
order, which is clearly unintelligible for human animals (Hobbes 1654
[1999], 38). It is important to recognize that an implication of the
second step of the strategy is that free will is not only compatible
with determinism but actually requires determinism (cf. Hume 1748
[1975] VIII). This was a widely shared assumption among compatibilists
up through the mid-twentieth century.

Spinoza’s Ethics (1677 [1992]) is an important
departure from the above dialectic. He endorses a strong form of
necessitarianism in which everything is categorically necessary
opposed to the weaker form of conditional necessity embraced by most
compatibilists, and he contends that there is no room in such a world
for divine or creaturely free will. Thus, Spinoza is a free will
skeptic. Interestingly, Spinoza is also keen to deny that the
nonexistence of free will has the dire implications often assumed. As
noted above, many in the modern period saw belief in free will and an
afterlife in which God rewards the just and punishes the wicked as
necessary to motivate us to act morally. According to Spinoza, so far
from this being necessary to motivate us to be moral, it actually
distorts our pursuit of morality. True moral living, Spinoza thinks,
sees virtue as its own reward (Part V, Prop. 42). Moreover, while free
will is a chimera, humans are still capable of freedom or
self-determination. Such self-determination, which admits of degrees
on Spinoza’s view, arises when our emotions are determined by
true ideas about the nature of reality. The emotional lives of the
free persons are ones in which “we desire nothing but that which
must be, nor, in an absolute sense, can we find contentment in
anything but truth. And so in so far as we rightly understand these
matters, the endeavor of the better part of us is in harmony with the
order of the whole of Nature” (Part IV, Appendix). Spinoza is an
important forerunner to the many free will skeptics in the twentieth
century, a position that continues to attract strong support (see
Strawson 1986; Double 1992; Smilansky 2000; Pereboom 2001, 2014; Levy
2011; Waller 2011; Caruso 2012; Vilhauer 2012. For further discussion
see the entry
skepticism about moral responsibility).

It is worth observing that in many of these disputes about the nature
of free will there is an underlying dispute about the nature of moral
responsibility. This is seen clearly in Hobbes (1654 [1999]) and early
twentieth century philosophers’ defense of compatibilism.
Underlying the belief that free will is incompatible with determinism
is the thought that no one would be morally responsible for any
actions in a deterministic world in the sense that no one would
deserve blame or punishment. Hobbes responded to this charge
in part by endorsing broadly consequentialist justifications of blame and
punishment: we are justified in blaming or punishing because these
practices deter future harmful actions and/or contribute to reforming
the offender (1654 [1999], 24–25; cf. Schlick 1939; Nowell-Smith
1948; Smart 1961). While many, perhaps even most, compatibilists have
come to reject this consequentialist approach to moral responsibility
in the wake of P. F. Strawson’s 1962 landmark essay
‘Freedom and Resentment’ (though see Vargas (2013) and
McGeer (2014) for contemporary defenses of compatibilism that appeal
to forward-looking considerations) there is still a general lesson to
be learned: disputes about free will are often a function of
underlying disputes about the nature and value of moral
responsibility.

2. The Nature of Free Will

2.1 Free Will and Moral Responsibility

As should be clear from this short discussion of the history of the
idea of free will, free will has traditionally been conceived of as a
kind of power to control one’s choices and actions. When an
agent exercises free will over her choices and actions, her choices
and actions are up to her. But up to her in what sense? As
should be clear from our historical survey, two common (and
compatible) answers are: (i) up to her in the sense that she is able
to choose otherwise, or at minimum that she is able not to choose or
act as she does, and (ii) up to her in the sense that she is the
source of her action. However, there is widespread controversy both
over whether each of these conditions is required for free will and if
so, how to understand the kind or sense of freedom to do otherwise or
sourcehood that is required. While some seek to resolve these
controversies in part by careful articulation of our experiences of
deliberation, choice, and action (Nozick 1981, ch. 4; van Inwagen
1983, ch. 1; O’Connor 2000, ch. 1), many seek to resolve these
controversies by appealing to the nature of moral responsibility. The
idea is that the kind of control or sense of up-to-meness involved in
free will is the kind of control or sense of up-to-meness relevant to
moral responsibility (Double 1992, 12; Ekstrom 2000, 7–8;
Smilansky 2000, 16; Widerker and McKenna 2003, 2; Vargas 2007, 128;
Nelkin 2011, 151–52; Levy 2011, 1; Pereboom 2014,
1–2). Indeed, some go so far as to define ‘free
will’ as ‘the strongest control condition—whatever
that turns out to be—necessary for moral responsibility’
(Wolf 1990, 3–4; Fischer 1994, 3; Mele 2006, 17). Given this
connection, we can determine whether the freedom to do otherwise and
the power of self-determination are constitutive of free will and, if
so, in what sense, by considering what it takes to be a morally
responsible agent. On these latter characterizations of free will,
understanding free will is inextricably linked to, and perhaps even
derivative from, understanding moral responsibility. And even those
who demur from this claim regarding conceptual priority typically see
a close link between these two ideas. Consequently, to appreciate the
current debates surrounding the nature of free will, we need to say
something about the nature of moral responsibility.

It is now widely accepted that there are different species of moral
responsibility. It is common (though not uncontroversial) to
distinguish moral responsibility as answerability from moral
responsibility as attributability from moral responsibility as
accountability (Watson 1996; Fischer and Tognazzini 2011;
Shoemaker 2011. See Smith (2012) for a critique of this taxonomy).
These different species of moral responsibility differ along three
dimensions: (i) the kind of responses licensed toward the responsible
agent, (ii) the nature of the licensing relation, and (iii) the
necessary and sufficient conditions for licensing the relevant kind of
responses toward the agent. For example, some argue that when an agent
is morally responsible in the attributability sense, certain
judgments about the agent—such as judgments concerning
the virtues and vices of the agent—are fitting, and that
the fittingness of such judgments does not depend on whether the agent
in question possessed the freedom to do otherwise (cf. Watson
1996).

While keeping this controversy about the nature of moral
responsibility firmly in mind (see the entry on
moral responsibility
for a
more detailed discussion of these issues), we think it is fair to say
that the most commonly assumed understanding of moral responsibility in
the historical and contemporary discussion of the problem of free will
is moral responsibility as accountability in something like
the following sense:

An agent \(S\) is morally accountable for performing an action
\(\phi\) \(=_{df.}\) \(S\) deserves praise if \(\phi\) goes beyond
what can be reasonably expected of \(S\) and \(S\) deserves blame if
\(\phi\) is morally wrong.

The central notions in this definition are praise,
blame, and desert. The majority of contemporary
philosophers have followed Strawson (1962) in contending that praising
and blaming an agent consist in experiencing (or at least being
disposed to experience (cf. Wallace 1994, 70–71)) reactive
attitudes or emotions directed toward the agent, such as gratitude,
approbation, and pride in the case of praise, and resentment,
indignation, and guilt in the case of blame. (See Sher (2006) and
Scanlon (2008) for important dissensions from this trend. See
the entry on blame
for a more detailed discussion.) These emotions, in turn, dispose
us to act in a variety of ways. For example, blame disposes us to
respond with some kind of hostility toward the blameworthy agent, such
as verbal rebuke or partial withdrawal of good will. But while these
kinds of dispositions are essential to our blaming someone, their
manifestation is not: it is possible to blame someone with very little
change in attitudes or actions toward the agent. Blaming someone might
be immediately followed by forgiveness as an end of the matter.

By ‘desert’, we have in mind what Derk Pereboom has
called basic desert:

The desert at issue here is basic in the sense that the agent would
deserve to be blamed or praised just because she has performed the
action, given an understanding of its moral status, and not, for
example, merely by virtue of consequentialist or contractualist
considerations. (2014, 2)

As we understand desert, if an agent deserves blame, then we have a
strong pro tanto reason to blame him simply in virtue of his
being accountable for doing wrong. Importantly, these reasons can be
outweighed by other considerations. While an agent may deserve blame,
it might, all things considered, be best to forgive him
unconditionally instead.

When an agent is morally responsible for doing something wrong, he is
blameworthy: he deserves hard treatment marked by resentment
and indignation and the actions these emotions dispose us toward, such
as censure, rebuke, and ostracism. However, it would seem unfair to
treat agents in these ways unless their actions were up to
them. Thus, we arrive at the core connection between free will
and moral responsibility: agents deserve praise or blame only if their
actions are up to them—only if they have free
will. Consequently, we can assess analyses of free will by their
implications for judgments of moral responsibility. We note that some
might reject the claim that free will is necessary for moral
responsibility (e.g., Frankfurt 1971; Stump 1988), but even for these
theorists an adequate analysis of free will must specify
a sufficient condition for the kind of control at play in
moral responsibility.

In what follows, we focus our attention on the two most commonly cited
features of free will: the freedom to do otherwise and sourcehood.
While some seem to think that free will consists exclusively in either
the freedom to do otherwise (van Inwagen 2008) or in sourcehood
(Zagzebski 2000), we think that the majority of philosophers hold that
free will involves both conditions—though philosophers often
emphasize one condition over the other depending on their dialectical
situation or argumentative purposes (cf. Watson 1987). In what
follows, we will describe the most common characterizations of these
two conditions.

2.2 The Freedom to Do Otherwise

For most newcomers to the problem of free will, it will seem obvious
that an action is up to an agent only if she had the freedom to do
otherwise. But what does this freedom come to? The freedom to do
otherwise is clearly a modal property of agents, but it is
controversial just what species of modality is at stake. It must be
more than mere possibility: to have the freedom to do
otherwise consists in more than the mere possibility of something
else’s happening. A more plausible and widely endorsed
understanding claims the relevant modality is ability or
power (Locke 1690 [1975], II.xx; Reid 1788 [1969],
II.i–ii; D. Locke 1973; Clarke 2009; Vihvelin 2013). But
abilities themselves seem to come in different varieties (Lewis 1976;
Horgan 1979; van Inwagen 1983, ch. 1; Mele 2003; Clarke 2009; Vihvelin
2013, ch. 1; Franklin 2015), so any claim that an agent has ‘the
ability to do otherwise’ is ambiguous or indeterminate unless
the sense of ability appealed to is spelled out. A satisfactory
account of the freedom to do otherwise owes us both an account of the
kind of ability in terms of which the freedom to do otherwise is
analyzed, and an argument for why this kind of ability (as opposed to
some other species) is the one constitutive of the freedom to do
otherwise. As we will see, philosophers sometimes leave this second
debt unpaid.

Simple Conditional Analysis: An agent \(S\) has the
ability to do otherwise if and only if, were \(S\) to choose to do
otherwise, then \(S\) would do otherwise.

Part of the attraction of this analysis is that it obviously
reconciles the freedom to do otherwise with determinism. While the
truth of determinism entails that one’s action is inevitable
given the past and laws of nature, there is nothing about determinism
that implies that if one had chosen otherwise, then one would
not do otherwise.

There are two problems with the Simple Conditional
Analysis. The first is that it is, at best, an analysis of
free action, not free will (cf. Reid 1788 [1969]; Chisholm 1966; 1976,
ch. 2; Lehrer 1968, 1976). It only tells us when an agent has the
ability to do otherwise, not when an agent has the ability to
choose to do otherwise. One might be tempted to think that
there is an easy fix along the following lines:

Simple Conditional Analysis*: An agent \(S\) has the
ability to choose otherwise if and only if, were \(S\) to desire or
prefer to choose otherwise, then \(S\) would choose otherwise.

The problem is that we often fail to choose to do things we want to
choose, even when it appears that we had the ability to choose
otherwise (one might think the same problem attends the original
analysis). Suppose that, in deciding how to spend my evening, I have a
desire to choose to read and a desire to choose to watch a movie.
Suppose that I choose to read. By all appearances, I had the ability
to choose to watch a movie. And yet, according to the Simple
Conditional Analysis*, I lack this freedom, since the
conditional ‘if I were to desire to choose to watch a movie,
then I would choose to watch a movie’ is false. I do desire to
choose to watch a movie and yet I do not choose to watch a movie. It
is unclear how to remedy this problem. On the one hand, we might
refine the antecedent by replacing ‘desire’ with
‘strongest desire’ (cf. Hobbes 1654 [1999], 1656 [1999];
Edwards 1754 [1957]). The problem is that this assumes, implausibly,
that we always choose what we most strongly desire (for criticisms of
this view see Reid 1788 [1969]; Campbell 1951; Wallace 1999; Holton
2009). On the other hand, we might refine the consequent by replacing
‘would choose to do otherwise’ with either ‘would
probably choose to do otherwise’ or ‘might choose to do
otherwise’. But each of these proposals is also problematic. If
‘probably’ means ‘more likely than not’, then
this revised conditional still seems too strong: it seems possible to
have the ability to choose otherwise even when one’s so choosing
is unlikely. If we opt for ‘might’, then the relevant
sense of modality needs to be spelled out.

Even if there are fixes to these problems, there is a yet deeper
problem with these analyses. There are some agents who clearly lack
the freedom to do otherwise and yet satisfy the conditional at the
heart of these analyses. That is, although these agents lack the
freedom to do otherwise, it is, for example, true of them
that if they chose otherwise, they would do
otherwise. Picking up on an argument developed by Keith Lehrer (1968;
cf. Campbell 1951; Broad 1952; Chisholm 1966), consider an
agoraphobic, Luke, who, when faced with the prospect of entering an
open space, is subject not merely to an irresistible desire to refrain
from intentionally going outside, but an irresistible desire to
refrain from even choosing to go outside. Given Luke’s
psychology, there is no possible world in which he suffers from his
agoraphobia and chooses to go outside. It may well nevertheless be
true that if Luke chose to go outside, then he would have
gone outside. After all, any possible world in which he chooses to go
outside will be a world in which he no longer suffers (to the same
degree) from his agoraphobia, and thus we have no reason to doubt that
in those worlds he would go outside as a result of his choosing to go
outside. The same kind of counterexample applies with equal force to
the conditional ‘if \(S\) desired to choose otherwise, then
\(S\) would choose otherwise’.

While simple conditional analyses admirably make clear the species of
ability to which they appeal, they fail to show that this species of
ability is constitutive of the freedom to do otherwise. Agents need a
stronger ability to do otherwise than characterized by such simple
conditionals. Some argue that the fundamental source of the above
problems is the conditional nature of these analyses
(Campbell 1951; Austin 1961; Chisholm 1966; Lehrer 1976; van Inwagen
1983, ch. 4). The sense of ability relevant to the freedom to do
otherwise is the ‘all-in sense’—that is, holding
everything fixed up to the time of the decision or action—and
this sense, so it is argued, can only be captured by a categorical
analysis of the ability to do otherwise:

Categorical Analysis: An agent \(S\) has the ability
to choose or do otherwise than \(\phi\) at time \(t\) if and only if
it was possible, holding fixed everything up to \(t\), that \(S\)
choose or do otherwise than \(\phi\) at \(t\).

This analysis gets the right verdict in Luke’s case. He lacks
the ability to do otherwise than refrain from choosing to go outside,
according to this analysis, because there is no possible world in
which he suffers from his agoraphobia and yet chooses to go
outside. Unlike the above conditional analyses,
the Categorical Analysis requires that we hold fixed
Luke’s agoraphobia when considering alternative
possibilities.

If the Categorical Analysis is correct, then free
will is incompatible with determinism. According to the thesis of
determinism, all deterministic possible worlds with the same pasts and
laws of nature have the same futures (Lewis 1979; van Inwagen 1983,
3). Suppose John is in deterministic world \(W\) and refrains from
raising his hand at time \(t\). Since \(W\) is deterministic, it
follows that any possible world \(W^*\) that has the same past and
laws up to \(t\) must have the same future, including John’s
refraining from raising his hand at \(t\). Therefore, John lacked the
ability, and thus freedom, to raise his hand.

This argument, carefully articulated in the late 1960s and early 1970s
by Carl Ginet (1966, 1990) and Peter van Inwagen (1975, 1983) and
refined in important ways by John Martin Fischer (1994), has come to
be known as the Consequence Argument. van Inwagen offers the following
informal statement of the argument:

If determinism is true, then our acts are the consequences of the laws
of nature and events in the remote past. But it is not up to us what
went on before we were born [i.e., we do not have the ability to change
the past], and neither is it up to us what the laws of nature are [i.e.,
we do not have the ability to break the laws of nature]. Therefore, the
consequences of these things (including our present acts) are not up to us.
(van Inwagen 1983, 16; cf. Fischer 1994, ch. 1)

Like the Simple Conditional Analysis, a virtue of
the Categorical Analysis is that it spells out
clearly the kind of ability appealed to in its analysis of the freedom
to do otherwise, but like the Simple Conditional
Analysis, critics have argued that the sense of ability it
captures is not the sense at the heart of free will. The objection
here, though, is not that the analysis is too permissive or weak, but
rather that it is too restrictive or strong.

While there have been numerous different replies along these lines
(e.g., Lehrer 1980; Slote 1982; Watson 1986. See the entry on
arguments for incompatibilism
for a more extensive discussion of and
bibliography for the Consequence Argument), the most influential of
these objections is due to David Lewis (1981). Lewis contended that
van Inwagen’s argument equivocated on ‘is able to break a
law of nature’. We can distinguish two senses of ‘is able
to break a law of nature’:

(Weak Thesis) I am able to do something such that, if I did it, a law
of nature would be broken.

(Strong Thesis) I am able to do something such that, if I did it, it
would constitute a law of nature’s being broken or would cause a
law of nature to be broken.

If we are committed to the Categorical Analysis,
then those desiring to defend compatibilism seem to be committed to the sense of ability in ‘is able to break
a law of nature’ along the lines of the strong thesis. Lewis
agrees with van Inwagen that it is “incredible” to think
humans have such an ability (Lewis 1981, 113), but maintains that
compatibilists need only appeal to the ability to break a law of nature
in the weak sense. While it is absurd to think that humans are able to
do something that is a violation of a law of nature or
causes a law of nature to be broken, there is nothing
incredible, so Lewis claimed, in thinking that humans are able to do
something such that if they did it, a law of nature would be
broken. In essence, Lewis is arguing that incompatibilists like van
Inwagen have failed to adequately motivate the restrictiveness of the
Categorical Analysis.

Some incompatibilists have responded to Lewis by contending that even
the weak ability is incredible (O’Connor 2000, ch.1; van Inwagen
2004). But there is a different and often overlooked problem for
Lewis: the weak ability seems to be too weak. Returning to the case of
John’s refraining from raising his hand, Lewis maintains that
the following three propositions are consistent:

(i)John is able to raise his hand.

(ii)A necessary condition for John’s raising his hand fails to obtain (i.e., that the laws of nature or past are different than they actually are).

(iii)John is not able to do anything that would constitute this necessary condition’s obtaining or cause this necessary condition to obtain (i.e., he is unable to do anything that would constitute or cause a law of nature to be broken or the past to be different).

One might think that (ii) and (iii) are incompatible with (i).
Consider again Luke, our agoraphobic. Suppose that his agoraphobia
affects him in such a way that he will only intentionally go outside
if he chooses to go outside, and yet his agoraphobia makes it
impossible for him to make this choice. In this case, a necessary
condition for Luke’s intentionally going outside is his choosing
to go outside. Moreover, Luke is not able to choose or cause himself
to choose to go outside. Intuitively, this would seem to imply that
Luke lacks the freedom to go outside. But this implication
does not follow for Lewis. From the fact that Luke is able to go
outside only if he chooses to go outside and the fact that Luke is not
able to choose to go outside, it does not follow, on
Lewis’s account, that Luke lacks the ability to go
outside. Consequently, Lewis’s account fails to explain why Luke
lacks the ability to go outside (cf. Speak 2011). (For other
important criticisms of Lewis, see Ginet [1990, ch. 5] and Fischer
[1994, ch. 4].)

While Lewis may be right that the Categorical
Analysis is too restrictive, his argument, all by itself,
doesn’t seem to establish this. His argument is successful only
if (a) he can provide an alternative analysis of ability that entails
that Luke’s agoraphobia robs him of the ability to go outside and
(b) does not entail that determinism robs John of the ability to raise
his hand (cf. Pendergraft 2010). Lewis must point out a principled
difference between these two cases. As should be clear from the above,
the Simple Conditional Analysis is of no help.
However, some recent work by Michael Smith (2003), Kadri Vihvelin
(2004; 2013), and Michael Fara (2008) have attempted to fill this gap.
What unites these theorists—whom Clarke (2009) has called the
‘new dispositionalists’—is their attempt to appeal to
recent advances in the metaphysics of dispositions to arrive at a
revised conditional analysis of the freedom to do otherwise. The most
perspicuous of these accounts is offered by Vihvelin (2004), who argues
that an agent’s having the ability to do otherwise is solely a
function of the agent’s intrinsic properties. (It is important to
note that Vihvelin [2013] has come to reject the view that free will
consists exclusively in the kind of ability analyzed below.) Building
on Lewis’s work on the metaphysics of dispositions, she arrives
at the following analysis of ability:

Revised Conditional Analysis of Ability: \(S\) has
the ability at time \(t\) to do \(X\) iff, for some intrinsic property
or set of properties \(B\) that \(S\) has at \(t\), for some time
\(t'\) after \(t\), if \(S\) chose (decided, intended, or tried) at
\(t\) to do \(X\), and \(S\) were to retain \(B\) until \(t'\),
\(S\)’s choosing (deciding, intending, or trying) to do \(X\)
and \(S\)’s having \(B\) would jointly be an \(S\)-complete
cause of \(S\)’s doing \(X\). (Vihvelin 2004, 438)

Lewis defines an ‘\(S\)-complete cause’ as “a cause
complete insofar as havings of properties intrinsic to [\(S\)] are
concerned, though perhaps omitting some events extrinsic to
[\(S\)]” (cf. Lewis 1997, 156). In other words, an
\(S\)-complete cause of \(S\)’s doing \(\phi\) requires that
\(S\) possess all the intrinsic properties relevant to \(S\)’s
causing \(S\)’s doing \(\phi\). This analysis appears to afford
Vihvelin the basis for a principled difference between agoraphobics
and merely determined agents. We must hold fixed an agent’s
phobias since they are intrinsic properties of agents, but we need not
hold fixed the laws of nature because these are not intrinsic
properties of agents. (It should be noted that the assumption that
intrinsic properties are wholly separable from the laws of nature is
disputed by ‘dispositional essentialists.’ See the entry on
metaphysics of causation.)
Vihvelin’s analysis appears to be restrictive enough to
exclude phobics from having the freedom to do otherwise, but
permissive enough to allow that some agents in deterministic worlds
have the freedom to do otherwise.

But appearances can be deceiving. The new dispositionalist claims
have received some serious criticism, with the majority of the
criticisms maintaining that these analyses are still too permissive
(Clarke 2009; Whittle 2010; Franklin 2011b). For example, Randolph
Clarke argues that Vihvelin’s analysis fails to overcome the
original problem with the Simple Conditional Analysis.
He writes, “A phobic agent might, on some occasion, be unable to
choose to A and unable to A without so choosing,
while retaining all that she would need to implement such a choice,
should she make it. Despite lacking the ability to choose to
A, the agent might have some set of intrinsic properties
B such that, if she chose to A and retained
B, then her choosing to A and her having B
would jointly be an agent-complete cause of her A-ing”
(Clarke 2009, p. 329).

The Categorical Analysis, and thus incompatibilism
about free will and determinism, remains an attractive option for many
philosophers precisely because it seems that compatibilists have yet to
furnish an analysis of the freedom to do otherwise that implies that
phobics clearly lack the ability to choose or do otherwise that is
relevant to moral responsibility and yet some merely determined agents
have this ability.

2.3 Freedom to Do Otherwise vs. Sourcehood Accounts

Some have tried to avoid these lingering problems for compatibilists
by arguing that the freedom to do otherwise is not required for free
will or moral responsibility. What matters for an agent’s
freedom and responsibility, so it is argued, is the source of
her action—how her action was brought about. The most prominent
strategy for defending this move appeals to ‘Frankfurt-style
cases’. In a ground-breaking piece, Harry Frankfurt (1969)
presented a series of thought experiments intended to show that it is
possible that agents are morally responsible for their actions and yet
they lack the ability to do otherwise. While Frankfurt (1971) took
this to show that moral responsibility and free will come
apart—free will requires the ability to do otherwise but moral
responsibility does not—if we define ‘free will’ as
‘the strongest control condition required for moral
responsibility’ (cf. Wolf 1990, 3–4; Fischer 1994, 3; Mele
2006, 17), then if Frankfurt-style cases show that moral
responsibility does not require the ability to do otherwise, then they
also show that free will does not require the ability to do
otherwise. Let us consider this challenge in more detail.

Here is a representative Frankfurt-style case:

Imagine, if you will, that Black is a quite nifty (and even generally
nice) neurosurgeon. But in performing an operation on Jones to remove
a brain tumor, Black inserts a mechanism into Jones’s brain
which enables Black to monitor and control Jones’s
activities. Jones, meanwhile, knows nothing of this. Black exercises
this control through a sophisticated computer which he has programmed
so that, among other things, it monitors Jones’s voting
behavior. If Jones were to show any inclination to vote for Bush,
then the computer, through the mechanism in Jones’s brain,
intervenes to ensure that he actually decides to vote for Clinton and
does so vote. But if Jones decides on his own to vote for Clinton,
the computer does nothing but continue to monitor—without
affecting—the goings-on in Jones’s head. (Fischer 2006,
38)

Fischer goes on to suppose that Jones “decides to vote for
Clinton on his own”, without any interference from Black, and
maintains that in such a case Jones is morally responsible for his
decision. Fischer draws two interrelated conclusions from this case.
The first, negative conclusion, is that the ability to do otherwise is
not necessary for moral responsibility. Jones is unable to refrain
from deciding to vote for Clinton, and yet, so long as Jones decides
to vote for Clinton on his own, his decision is free and one for which
he is morally responsible. The second, positive conclusion, is that
freedom and responsibility are functions of the
actual sequence. What matters for an agent’s freedom
and moral responsibility is not what might have happened, but how his
action was actually brought about. What matters is not whether the
agent had the ability to do otherwise, but whether he was the source
of his actions.

The success of Frankfurt-style cases is hotly contested. An early
and far-reaching criticism is due to David Widerker (1995), Carl Ginet
(1996), and Robert Kane (1996, 142–43). According to this
criticism, proponents of Frankfurt-style cases face a dilemma: either
these cases assume that the connection between the indicator (in our
case, the absence of Jones’s showing any inclination to decide to
vote for Bush) and the agent’s decision (here, Jones’s
deciding to vote for Clinton) is deterministic or not. If the
connection is deterministic, then Frankfurt-style cases cannot be
expected to convince incompatibilists that the ability to do otherwise
is not necessary for moral responsibility and/or free will, since
Jones’s action will be deterministically brought about by factors
beyond his control, leading incompatibilists to conclude that Jones is
not morally responsible for his decision. But if the connection is
nondeterministic, then it is possible even in the absence of showing
any inclination to decide to vote for Bush, that Jones decides to vote
for Bush, and so he retains the ability to do otherwise. Either way
Frankfurt-style cases fail to show that Jones is both morally
responsible for his decision and yet is unable to do otherwise.

While some have argued that even Frankfurt-style cases that assume
determinism are effective (see, e.g., Fischer 1999, 2010, 2013 and
Haji and McKenna 2004 and for criticisms of this approach, see Goetz
2005, Palmer 2005, 2014, Widerker and Goetz 2013, and Cohen 2017), the
majority of proponents of Frankfurt-style cases have attempted to
revise these cases so that they are explicitly nondeterministic and
yet still show that the agent was morally responsible even though he
lacked the ability to do otherwise—or, at least that he lacked
any ability to do otherwise that could be relevant
to grounding the agent’s moral responsibility (see,
e.g., Mele and Robb 1998, 2003, Pereboom 2001, 2014, McKenna 2003,
Hunt 2005, and for criticisms of these cases see Ginet 2002, Timpe
2006, Widerker 2006, Franklin 2011c, Moya 2011, Palmer 2011, 2013,
Robinson 2014, Capes 2016, Capes and Swenson 2017, and Elzein
2017).

Supposing that Frankfurt-style cases are successful, what exactly
do they show? In our view, they show neither that free will
and moral responsibility do not require an ability to do otherwise
in any sense nor that compatibilism is true. Frankfurt-style
cases are of clear help to the compatibilists’ position (though
see Speak 2007 for a dissenting opinion). The Consequence Argument
raises a powerful challenge to the cogency of compatibilism. But if
Frankfurt-style cases are successful, agents can act freely in the
sense relevant to moral responsibility while lacking the ability to do
otherwise in the all-in sense. This allows compatibilists to concede
that the all-in ability to do otherwise is incompatible with
determinism, and yet insist that it is irrelevant to the question of
the compatibility of determinism with moral responsibility (and
perhaps even free will, depending on how we define this) (cf. Fischer
1987, 1994. For a challenge to the move from not strictly necessary to
irrelevant, see O’Connor [2000, 20–22] and in reply,
Fischer [2006, 152–56].). But, of course, showing that an
argument for the falsity of compatibilism is irrelevant does not show
that compatibilism is true. Indeed, many incompatibilists maintain
that Frankfurt-style cases are successful and defend incompatibilism
not via the Consequence Argument, but by way of arguments that attempt
to show that agents in deterministic worlds cannot be the
‘source’ of their actions in the way that moral
responsibility requires (Stump 1999; Zagzebski 2000; Pereboom 2001,
2014). Thus, if successful, Frankfurt-style cases would be at best the
first step in defending compatibilism. The second step must offer an
analysis of the kind of sourcehood constitutive of free will that
entails that free will is compatible with determinism (cf. Fischer
1982).

Furthermore, while proponents of Frankfurt-style cases often maintain
that these cases show that no ability to do otherwise is necessary for
moral responsibility (“I have employed the Frankfurt-type
example to argue that this sense of control [i.e. the one required for
moral responsibility] need not involve any alternative
possibilities” [Fischer 2006, p. 58; emphasis ours]), we believe
that this conclusion overreaches. At best, Frankfurt-style cases
show that the ability to do otherwise in the all-in
sense—in the sense defined by the Categorical
Analysis—is not necessary for free will or moral
responsibility (cf. Franklin 2015). To appreciate this, let us assume
that in the above Frankfurt-style case Jones lacks the ability to do
otherwise in the all-in sense: there is no possible world in which we
hold fixed the past and laws and yet Jones does otherwise, since all
such worlds include Black and his preparations for preventing Jones
from doing otherwise should Jones show any inclination. Even if this
is all true, it should take only a little reflection to recognize that
in this case Jones is able to do otherwise in certain weaker senses we
might attach to that phrase, and compatibilists in fact still think
that the ability to do otherwise in some such senses is necessary for
free will and moral responsibility. Consequently, even though
Frankfurt-style cases have, as a matter of fact, moved many
compatibilists away from emphasizing ability to do otherwise to
emphasizing sourcehood, we suggest that this move is best seen as a
weakening of the ability-to-do-otherwise condition on moral
responsibility. (A potentially important exception to
this claim is Sartorio [2016], who appealing to some controversial
ideas in the metaphysics of causation appears to argue that no sense
of the ability to do otherwise is necessary for control in the sense
at stake for moral responsibility, but instead what matters is whether
the agent is the cause of the action. We simply note that
Sartorio’s account of causation is a modal one [see especially
Sartorio (2016, 94–95, 132–37)] and thus it is far from
clear that her account of freedom and responsibility is really an
exception.)

2.4 Compatibilist Accounts of Sourcehood

In this section, we will assume that Frankfurt-style cases are
successful in order to consider two prominent compatibilist attempts
to construct analyses of the sourcehood condition (though see
the entry on
compatibilism
for a more systematic survey of compatibilist
theories of free will). The first, and perhaps most popular,
compatibilist model is a reasons-responsiveness model. According to
this model, an agent’s action \(\phi\) is free just in case the
agent or manner in which the action is brought about is responsive to
the reasons available to the agent at the time of action. While
compatibilists develop this kind of account in different ways, the
most detailed proposal is due to John Martin Fischer (1994, 2006,
2010, 2012; Fischer and Ravizza 1998. For similar compatibilist
treatments of reasons-responsiveness, see Wolf 1990, Wallace 1994,
Haji 1998, Nelkin 2011, McKenna 2013, Vargas 2013, Sartorio
2016). Fischer and Ravizza argue that an agent’s action is free
and one for which he is morally responsible only if the mechanism that
issued in the action is moderately reasons-responsive (Fischer and
Ravizza 1998, ch. 3). By ‘mechanism’, Fischer and Ravizza
simply mean “the way the action was brought about”
(38). One mechanism they often discuss is practical deliberation. For
example, in the case of Jones discussed above, his decision to vote
for Clinton on his own was brought about by the process of practical
deliberation. What must be true of this process, this mechanism, for
it to be moderately reasons-responsive? Fischer and Ravizza maintain
that moderate reasons-responsiveness consists in two conditions:
reasons-receptivity and reasons-reactivity. A mechanism’s
reasons-receptivity depends on the agent’s cognitive capacities,
such as being capable of understanding moral reasons and the
implications of their actions (69–73). The second condition is
more important for us in the present context. A mechanism’s
reasons-reactivity depends on how the mechanism would react
given different reasons for action. Fischer and Ravizza argue that
the kind of reasons-reactivity at stake is weak reasons-reactivity,
where this merely requires that there is some possible world in which
the laws of nature remain the same, the same mechanism operates,
there is a sufficient reason to do otherwise, and the mechanism brings
about this the alternative action in response to this sufficient
reason (73–76). On this analysis, while Jones, due to the
activity of Black, lacks the all-in sense of the ability to do
otherwise, he is nevertheless morally responsible for deciding to vote
for Clinton because his action finds its source in Jones’s
practical deliberation that is moderately
reasons-responsive.

Fischer and Ravizza offer a novel and powerful theory of freedom and
responsibility, one that has shifted the focus of recent debate to
questions of sourcehood. Moreover, one might argue that this theory is
a clear improvement over classical compatibilism with respect to
handling cases of phobia. By focusing on mechanisms, Fischer and
Ravizza can argue that our agoraphobic Luke is not morally responsible
for deciding to refrain from going outside because the mechanism that
issues in this action—namely his agoraphobia—is not
moderately reasons-responsive. There is no world with the same laws of
nature as our own, this mechanism operates, and yet it reacts to a
sufficient reason to go outside. No matter what reasons there are for
Luke to go outside, when acting on this mechanism, he will always
refrain from going outside (cf. Fischer 1987, 74).

Before turning to our second compatibilist model, it is worth noting
that it would be a mistake to think that Fischer and Ravizza’s
account is a sourcehood account to the exclusion of the ability to do
otherwise in any sense. As we have just seen, Fischer and
Ravizza place clear modal requirements on mechanisms that
issue in actions with respect to which agents are free and morally
responsible. Indeed, this should be clear from the very idea of
reasons-responsiveness. Whether one is responsive depends not merely
on how one does respond, but also on how one would
respond. Thus, any account that makes reasons-responsiveness an
essential condition of free will is an account that makes the ability
to do otherwise, in some sense, necessary for free will (Fischer
[forthcoming] concedes this point, though, as noted above, the reader
should consider Sartorio [2016] as a potential counterexample to this
claim).

The second main compatibilist model of sourcehood is an identification
model. Accounts of sourcehood of this kind lay stress on
self-determination or autonomy: to be the source of her action the
agent must self-determine her action. Like the contemporary discussion
of the ability to do otherwise, the contemporary discussion of the
power of self-determination begins with the failure of classical
compatibilism to produce an acceptable definition. According to
classical compatibilists, self-determination simply consists in the
agent’s action being determined by her strongest motive. On the
assumption that some compulsive agents’ compulsions operate by
generating irresistible desires to act in certain ways, the classical
compatibilist analysis of self-determination implies that these
compulsive actions are self-determined. While Hobbes seems willing to
accept this implication (1656 [1999], 78), most contemporary
compatibilists concede that this result is unacceptable.

Beginning with the work of Harry Frankfurt (1971) and Gary Watson
(1975), many compatibilists have developed identification accounts of
self-determination that attempt to draw a distinction between an
agent’s desires or motives that are internal to the agent and
from those that are external. The idea is that while agents are not
(or at least may not be) identical to any motivations (or bundle of
motivations), they are identified with a subset of their
motivations, rendering these motivations internal to the agent in such
a way that any actions brought about by these motivations are
self-determined. The identification relation is not an
identity relation, but something weaker (cf. Bratman 2000, 39n12). What
the precise nature of the identification relation is and to which
attitudes an agent stands in this relation is hotly disputed.
Lippert-Rasmussen (2003) helpfully divides identification accounts into
two main types. The first are “authority” accounts,
according to which agents are identified with attitudes that are
authorized to speak for them (386). The second are
authenticity accounts, according to which agents are identified with
attitudes that reveal who they truly are (368). (But see
Shoemaker 2015 for an ecumenical account of identification that blends
these two accounts.) Proposed attitudes to which agents are said to
stand in the identification relation include higher-order desires
(Frankfurt 1971), cares or loves (Frankfurt 1993, 1994; Shoemaker 2003;
Jaworska 2007; Sripada 2016), self-governing policies (Bratman 2000),
the desire to make sense of oneself (Velleman 1992, 2009), and
perceptions (or judgments) of the good (or best) (Watson 1975; Stump
1988; Ekstrom 1993; Mitchell-Yellin 2015).

The distinction between internal and external motivations allows
identification theorists to enrich classical compatibilists’
understanding of constraint, while remaining compatibilists about free
will and determinism. According to classical compatibilists, the only
kind of constraint is external (e.g., broken cars and broken legs),
but addictions and phobias seem just as threatening to free will.
Identification theorists have the resources to concede that some
constraints are internal. For example, they can argue that our
agoraphobic Luke is not free in refraining from going outside even
though this decision was caused by his strongest desires because he is
not identified with his strongest desires. On compatibilist
identification accounts, what matters for self-determination is not
whether our actions are determined or undetermined, but whether they
are brought about by motives with which the agent is identified:
exercises of the power of self-determination consists in an
agent’s actions being brought about, in part, by an
agent’s motives with which she is identified. (It is important
to note that while we have distinguished reasons-responsive accounts
from identification accounts, there is nothing preventing one from
combing both elements in a complete analysis of free will.)

Even if these reasons-responsive and identification compatibilist
accounts of sourcehood might successfully side-step the Consequence
Argument, they must come to grips with a second incompatibilist
argument: the Manipulation Argument. The general problem raised by
this line of argument is that whatever proposed compatibilist
conditions for an agent \(S\)’s being free with respect to, and
morally responsible for, some action \(\phi\), it will seem that
agents can be manipulated into satisfying these conditions with
respect to \(\phi\) and, yet, precisely because they are manipulated
into satisfying these conditions, their freedom and responsibility
seem undermined. The two most influential forms of the Manipulation
Argument are Pereboom’s Four-case Argument (2001, ch. 4; 2014,
ch. 4) and Mele’s Zygote Argument (2006, ch. 7. See Todd 2010,
2012 for developments of Mele’s argument). As the structure of
Mele’s version is simpler, we will focus on it.

Imagine a goddess Diana who creates a zygote \(Z\) in Mary in some
deterministic world. Suppose that Diana creates \(Z\) as she does
because she wants Jones to be murdered thirty years later. From her
knowledge of the laws of nature in her world and her knowledge of the
state of the world just prior to her creating \(Z\), she knows that a
zygote with precisely \(Z\)’s constitution located in Mary will
develop into an agent Ernie who, thirty years later, will murder Jones
as a result of his moderately reasons-responsive mechanism and on the
basis of motivations with which he is identified (whatever those might
be). Suppose Diana succeeds in her plan and Ernie murders Jones as a
result of her manipulation.

Many judge that Ernie is not morally responsible for murdering Jones
even though he satisfies both the reasons-responsive and
identification criteria. There are two possible lines of reply open to
compatibilists. On the soft-line reply, compatibilists attempt to
show that there is a relevant difference between manipulated agents
such as Ernie and agents who satisfy their account (McKenna 2008,
470). For example, Fischer and Ravizza propose a second condition on
sourcehood: in addition to a mechanism’s being moderately
reasons-responsive, an agent is morally responsible for the output of
such a mechanism only if the agent has come to take responsibility for
the mechanism, where an agent has taken responsibility for a mechanism
\(M\) just in case (i) she believes that she is an agent when acting
from \(M\), (ii) she believes that she is an apt target for blame and
praise for acting from \(M\), and (iii) her beliefs specified in (i)
and (ii) are “based, in an appropriate way, on [her]
evidence” (Fischer and Ravizza 1998, 238). The problem with this
reply is that we can easily imagine Diana creating Ernie so that his
murdering Jones is a result not only of a moderately
reasons-responsive mechanism, but also a mechanism for which he has
taken responsibility. On the hard-line reply, compatibilists concede
that, despite initial appearances, the manipulated agent is free and
morally responsible and attempt to ameliorate the seeming counterintuitiveness of this concession (McKenna
2008, 470–71). Here compatibilists might point out that the idea
of being manipulated is worrisome only so long as the manipulators are
interfering with an agent’s development. But if the manipulators
simply create a person, and then allow that person’s life to
unfold without any further inference, the manipulators’ activity
is no threat to freedom (McKenna 2008; Fischer 2011; Sartorio 2016,
ch. 5). (For other responses to the Manipulation Argument, see Kearns
2012; Sripada 2012; McKenna 2014.)

2.5 Libertarian Accounts of Sourcehood

Despite these compatibilist replies, to some the idea that the
entirety of a free agent’s life can be determined, and
in this way controlled, by another agent will seem incredible. Some
take the lesson of the Manipulation Argument to be that no
compatibilist account of sourcehood or self-determination is
satisfactory. True sourcehood—the kind of sourcehood that can
actually ground an agent’s freedom and
responsibility—requires, so it is argued, that one’s
action not be causally determined by factors beyond one’s
control.

Libertarians, while united in endorsing this negative condition on
sourcehood, are deeply divided concerning which further positive
conditions may be required. It is important to note that while
libertarians are united in insisting that compatibilist accounts of
sourcehood are insufficient, they are not committed to thinking that
the conditions of freedom spelled out in terms either of
reasons-responsiveness or of identification are not necessary. For
example, Stump (1988, 1996, 2010) builds a sophisticated libertarian
model of free will out of resources originally developed within
Frankfurt’s identification model (see also Ekstrom 1993, 2000;
Franklin 2014) and nearly all libertarians agree that exercises of
free will require agents to be reasons-responsive (e.g., Kane 1996;
O’Connor 2009a; Clarke 2003, chs. 8–9; Franklin 2018, ch. 2). Moreover, while
this section focuses on libertarian accounts of sourcehood, we remind
readers that most (if not all) libertarians think that the freedom to
do otherwise is also necessary for free will and moral
responsibility.

There are three main libertarian options for understanding sourcehood
or self-determination: non-causal libertarianism (Ginet 1990, 2008;
McCann 1998; Lowe 2008; Goetz 2009; Pink 2017), event-causal
libertarianism (Wiggins 1973; Kane 1996, 1999, 2011, 2016; Mele 1995,
chs. 11–12; 2006, chs. 4–5; 2017; Ekstrom 2000,
forthcoming; Clarke 2003, chs. 2–6; Franklin 2018), and
agent-causal libertarianism (Reid 1788 [1969]; Chisholm 1966, 1976;
Taylor 1966; O’Connor 2000, 2005, 2009a; Clarke 1993; 1996;
2003, chs. 8–10; Griffith 2010; Steward 2012). Non-causal
libertarians contend that exercises of the power of self-determination
need not (or perhaps even cannot) be caused or causally
structured. According to this view, we control our volition or choice
simply in virtue of its being ours—its occurring in us. We do
not exert a special kind of causality in bringing it about; instead,
it is an intrinsically active event, intrinsically something
we do. While there may be causal influences upon our choice,
there need not be, and any such causal influence is wholly irrelevant
to understanding why it occurs. Reasons provide an autonomous,
non-causal form of explanation. Provided our choice is not wholly
determined by prior factors, it is free and under our control simply
in virtue of being ours. Non-causal views have failed to garner wide
support among libertarians since, for many,
self-determination seems to be an essentially causal notion
(cf. O’Connor 1993; 2000, ch. 2; Mele 2000; Clarke 2003, ch.
2).

Most libertarians endorse an event-causal or agent-causal account of
sourcehood. Both these accounts maintain that exercises of the power
of self-determination consist partly in the agent’s bringing
about her choice or action, but they disagree on how to analyze an
agent’s bringing about her choice. While event-causal
libertarianism admits of different species, at the heart of this view
is the idea that self-determining an action requires, at minimum, that
the agent cause the action and that an agent’s causing his
action is wholly reducible to mental states and other events
involving the agent nondeviantly causing his action. Consider an
agent’s raising his hand. According to the event-causal model at
its most basic level, an agent’s raising his hand consists in
the agent’s causing his hand to rise and his causing his hand to
rise consists in apt mental states and events involving the
agent—such as the agent’s desire to ask a question and his
belief that he can ask a question by raising his
hand—nondeviantly causing his hand to rise. (The
nondeviance clause is required since it seems possible that an event
be brought about by one’s desires and beliefs and yet not be
self-determined, or even an action for that matter, due to the unusual
causal path leading from the desires and beliefs to action. Imagine a
would-be accomplice of an assassin believes that his dropping his
cigarette is the signal for the assassin to shoot his intended victim
and he desires to drop his cigarette and yet this belief and desire so
unnerve him that he accidentally drops his cigarette. While the event
of dropping the cigarette is caused by a relevant desire and belief it
does not seem to be self-determined and perhaps is not even an action
[cf. Davidson 1973].) To fully spell out this account, event-causal
libertarians must specify which mental states and events are apt (cf.
Brand 1979)—which mental states and events are the springs of
self-determined actions—and what nondeviance consists in (cf.
Bishop 1989). (We note that this has proven very difficult, enough so
that some take the problem to spell doom for event-causal theories of
action. Such philosophers [e.g., Taylor 1966 and Sehon 2005] take
agential power to be conceptually and/or ontologically primitive and
understand reasons explanations of action in irreducibly teleological
terms. See Stout 2010 for a brisk survey of discussions of this
topic.) For ease, in what follows we will assume that apt mental
states are an agent’s reasons that favor the action.

Event-causal libertarians, of course, contend that self-determination
requires more than nondeviant causation by agents’ reasons: for
it is possible that agents’ actions in deterministic worlds are
nondeviantly caused by apt mental states and
events. Self-determination requires nondeterministic
causation, in a nondeviant way, by an agent’s reasons. While
historically many have thought that nondeterministic causation is
impossible (Hobbes 1654 [1999], 1656 [1999]; Hume 1740 [1978], 1748
[1975]), with the advent of quantum physics and, from a very different
direction, an influential essay by G. E. M. Anscombe (1971), it is now
widely assumed that nondeterministic (or probabilistic) causation is
possible. There are two importantly different ways to understand
nondeterministic causation: as the causation of probability or as the
probability of causation (cf. Jacobs and O’Connor 2013). Under
the causation of probability model, a nondeterministic cause \(C\)
causes (or causally contributes to) the objective probability of the
outcome’s occurring rather than the outcome itself. On this
account, \(S\)’s reasons do not cause his decision but there
being a certain antecedent objective probability of its occurring, and
the decision itself is uncaused. On the competing probability of
causation model, a nondeterministic cause \(C\) causes the outcome of
a nondeterministic process. Given that \(C\) is a nondeterministic
cause of the outcome, it was possible given the exact same past and
laws of nature that \(C\) not cause the outcome (perhaps because it
was possible that some other event cause some other outcome)—the
probability of this causal transaction’s occurring was less than
\(1\). Given that event-causal libertarians maintain that
self-determined actions, and thus free actions, must be caused, they
are committed to the probability of causation model of
nondeterministic causation (cf. Franklin 2018, 25–26). (We note
that Balaguer [2010] is skeptical of the above distinction, and it is
thus unclear whether he should best be classified as a non-causal or
event-causal libertarian though see Balaguer [2014] for evidence that
it is best to treat him as a non-causalist.) Consequently, according
to event-causal libertarians, when an agent \(S\) self-determines his
choice \(\phi\), then \(S\)’s reasons \(r_1\)
nondeterministically cause (in a nondeviant way) \(\phi\), and it was
possible, given the past and laws, that \(r_1\) not have caused
\(\phi\), but rather some of \(S\)’s other reasons \(r_2\)
nondeterministically caused (in a nondeviant way) a different action
\(\psi\).

Agent-casual libertarians contend that the event-causal picture fails
to capture self-determination, for it fails to accord the agent with a
power to settle what she does. Pereboom offers a forceful
statement of this worry:

On an event-causal libertarian picture, the relevant causal conditions
antecedent to the decision, i.e., the occurrence of certain
agent-involving events, do not settle whether the decision will occur,
but only render the occurrence of the decision about \(50\%\)
probable. In fact, because no occurrence of antecedent events settles
whether the decision will occur, and only antecedent events are
causally relevant,
nothing settles whether the decision will occur. (Pereboom
2014, 32; cf. Watson 1987, 1996; O’Connor 1993, 1996; Clarke
2003, ch. 8; 2011; Griffith 2010; Shabo 2011, 2013; Steward 2012, ch.
3; Schlosser 2014)

On the event-causal picture, the agent’s causal contribution to
her actions is exhausted by the causal contribution of her reasons,
and yet her reasons leave open which decisions she will make, and this
seems insufficient for self-determination.

But what more must be added? Agent-causal libertarians maintain that
self-determination requires that the agent herself play a
causal role over and above the causal role played by her reasons. Some
agent-causal libertarians deny that an agent’s reasons play any
direct causal role in bringing about an agent’s self-determined
actions (Chisholm 1966; O’Connor 2000, ch. 5; 2009a), whereas
others allow or even require that self-determined actions be caused in
part by the agent’s reasons (Clarke 2003, ch. 9; Steward 2012,
ch. 3). But all agent-causal libertarians insist that exercises of the
power of self-determination do not reduce to nondeterministic
causation by apt mental states: agent-causation does not reduce to
event-causation.

Agent-causal libertarianism seems to capture an aspect of
self-determination that neither the above compatibilists accounts nor
event-causal libertarian accounts capture. (Some compatibilists even
accept this and try to incorporate agent-causation into a
compatibilist understanding of free will. See Markosian 1999, 2012;
Nelkin 2011.) These accounts reduce the causal role of the self to
states and events to which the agent is not identical (even if he is
identified with them). But how can self-determination of my
actions wholly reduce to determination of my actions by
things other than the self? Richard Taylor nicely expresses
this intuition: “If I believe that something not identical to
myself was the cause of my behavior—some event wholly external
to myself, for instance, or even one internal to myself, such as a
nerve impulse, volition, or whatnot—then I cannot regard the
behavior as being an act of mine, unless I further believed that I was
the cause of that external or internal event” (1974, 55;
cf. Franklin 2016).

Despite its powerful intuitive pull for some, many have argued that
agent-causal libertarianism is obscure or even incoherent. The stock
objection used to be that the very idea of
agent-causation—causation by agents that is not reducible to
causation by mental states and events involving the agent—is
incoherent, but this objection has become less common due to
pioneering work by Chisholm (1966, 1976), Taylor (1974),
O’Connor (1995a, 2000, 2005, 2009a), and Clarke (1993, 1996,
2003) (for helpful critical discussions of these worries see Clarke
2003, ch. 10; O’Connor 2011; and Steward 2012, ch. 8). More
common objections now concern, first, how to understand the
relationship between agent-causation and an agent’s reasons (or
motivations in general), and, second, the empirical adequacy of
agent-causal libertarianism. With respect to the first worry, it is
widely assumed that the only (or at least best) way to understand
reasons-explanation and motivational influence is within a causal
account of reasons, where reasons cause our actions (Davidson 1963;
Mele 1992). If agent-causal libertarians accept that self-determined
actions, in addition to being agent-caused, must also be caused by
agents’ reasons that favored those actions, then agent-causal
libertarians need to explain how to integrate these causes (for a
sophisticated attempt to do just this, see Clarke 2003, ch. 8). Given
that these two causes seem distinct, is it not possible that the agent
cause his decision to \(\phi\) and yet the agent’s reasons
simultaneously cause an incompatible decision to \(\psi\)? If
agent-causal libertarians side-step this difficult question by denying
that reasons cause action, then they must explain how reasons can
explain and motivate action without causing it; and this has turned
out to be no easy task (but for a sophisticated attempt to do just
this, see O’Connor 2000, 2009a; for more general attempts to
understand reasons-explanation and motivation within a non-causal
framework see Schueler 1995, 2003; Sehon 2005). For further discussion
see the entry on
incompatibilist (nondeterministic) theories of free will.

Finally, we note that some recent philosophers have questioned the
presumed difference between event- and agent-causation by arguing that
all causation is object or substance causation. They argue
that the dominant tendency to understand ‘garden variety’
causal transactions in the world as relations between events is an
unfortunate legacy of David Hume’s rejection of substance and
causation as basic metaphysical categories. On the competing
metaphysical picture of the world, the event or state of an
object’s having some property such as mass is its having a
causal power, which in suitable circumstances it exercises to bring
about a characteristic effect. Applied to human agents in an account
of free will, the account suggests a picture on which an agent’s
having desires, beliefs, and intentions are rational powers to will
particular courses of action, and where the agent’s willing is
not determined in any one direction, she wills freely. An advantage
for the agent-causalist who embraces this broader metaphysics is
‘ideological’ parsimony. For different developments and
defenses of this approach, see Lowe (2008), Swinburne (2013), and
Jacobs and O’Connor (2013).

3. Do We Have Free Will?

Most philosophers theorizing about free will take themselves to be
attempting to analyze a near-universal power of mature human beings.
But as we’ve noted above, there have been free will skeptics in
both ancient and (especially) modern times. (Israel 2001 highlights a
number of such skeptics in the early modern period.) In this section,
we summarize the main lines of argument both for and against the
reality of human freedom of will.

3.1 Arguments Against the Reality of Free Will

There are both a priori and empirical arguments against free will (See
the entry on
skepticism about moral responsibility).
Several of these start with an argument that free will is incompatible
with causal determinism, which we will not rehearse here. Instead, we
focus on arguments that human beings lack free will, against the
background assumption that freedom and causal determinism are
incompatible.

The most radical a priori argument is that free will is not merely
contingently absent but is impossible. In recent decades, this
argument is most associated with Galen Strawson (1986, ch. 2; 1994,
2002). Strawson associates free will with being ‘ultimately
morally responsible’ for one’s actions. He argues that,
because how one acts is a result of, or explained by, “how one
is, mentally speaking” (\(M\)), for one to be responsible for
that choice one must be responsible for \(M\). To be responsible for
\(M\), one must have chosen to be \(M\) itself—and that not
blindly, but deliberately, in accordance with some reasons
\(r_1\). But for that choice to be a responsible one, one must have
chosen to be such as to be moved by \(r_1\), requiring some further
reasons \(r_2\) for such a choice. And so on, ad
infinitum. Free choice requires an impossible infinite regress of
choices to be the way one is in making choices.

There have been numerous replies to Strawson’s argument. Mele
(1995, 221ff.) argues that Strawson misconstrues the locus of freedom
and responsibility. Freedom is principally a feature of our actions,
and only derivatively of our characters from which such actions
spring. The task of the theorist is to show how one is in rational,
reflective control of the choices one makes, consistent with there
being no freedom-negating conditions. While this seems right, when
considering those theories that make one’s free control to
reside directly in the causal efficacy of one’s reasons (such as
compatibilist reasons-responsive accounts or event-causal
libertarianism), it is not beside the point to reflect on how one came
to be that way in the first place and to worry that such reflection
should lead one to conclude that true responsibility (and hence
freedom) is undermined, since a complete distal source of any action
may be found external to the agent. Clarke (2003, 170–76) argues
that an effective reply may be made by indeterminists, and, in
particular, by nondeterministic agent-causal theorists. Such theorists
contend that (i) aspects of ‘how one is, mentally
speaking’, fully explain an agent’s choice
without causally determining it and (ii) the agent himself causes the
choice that is made (so that the agent’s antecedent state, while
grounding an explanation of the action, is not the complete causal
source of it). Since the agent’s exercise of this power is
causally undetermined, it is not true that there is a sufficient
‘ultimate’ source of it external to the agent. Finally,
Mele (2006, 129–34, and 2017, 212–16) and O’Connor
(2005, 2009b) suggest that freedom and moral responsibility come in
degrees and grow over time, reflecting the fact that ‘how one
is, mentally speaking’ is increasingly shaped by one’s own
past choices. Furthermore, some choices for a given individual may
reflect more freedom and responsibility than others, which may be the
kernel of truth behind Strawson’s sweeping argument. (For
discussion of the ways that nature, nurture, and contingent
circumstances shape our behavior and raise deep issues concerning
the extent of our freedom and responsibility, see Levy 2011
and Russell 2017, chs. 10–12.)

A second family of arguments against free will contend that, in one
way or another, nondeterministic theories of freedom entail either
that agents lack control over their choices or that the choices cannot
be adequately explained. These arguments are variously called the
‘Mind’, ‘Rollback’, or ‘Luck’
argument, with the latter admitting of several versions. (For
statements of such arguments, see van Inwagen 1983, ch. 4; 2000; Haji
2001; Mele 2006; Shabo 2011, 2013, forthcoming; Coffman 2015). We note
that some philosophers advance such arguments not as parts of a
general case against free will, but merely as showing the inadequacy
of specific accounts of free will [see, e.g., Griffith 2010].) They
each describe imagined cases—individual cases, or comparison of
intra- or inter-world duplicate antecedent conditions followed by
diverging outcomes—designed to elicit the judgment that the
occurrence of a choice that had remained unsettled given all
prior causal factors can only be a ‘matter of chance’,
‘random’, or ‘a matter of luck’. Such terms
have been imported from other contexts and have come to function as
quasi-technical, unanalyzed concepts in these debates, and it is
perhaps more helpful to avoid such proxies and to conduct the debates
directly in terms of the metaphysical notion of control and epistemic
notion of explanation. Where the arguments question whether an
undetermined agent can exercise appropriate control over the choice he
makes, proponents of nondeterministic theories often reply that
control is not exercised prior to, but at the time of the
choice—in the very act of bringing it about (see, e.g., Clarke
2005 and O’Connor 2007). Where the arguments question whether
undetermined choices can be adequately explained, the reply often
consists in identifying a form of explanation other than the form
demanded by the critic—a ‘noncontrastive’
explanation, perhaps, rather than a ‘contrastive’
explanation, or a species of contrastive explanation consistent with
indeterminism (see, e.g., Kane 1999; O’Connor 2000, ch. 5;
Clarke, 2003, ch. 8; and Franklin 2011a; 2018, ch. 5).

We now consider empirical arguments against human freedom. Some of
these stem from the physical sciences (while making assumptions
concerning the way physical phenomena fix psychological phenomena) and
others from neuroscience and psychology.

It used to be common for philosophers to argue that there is empirical
reason to believe that the world in general is causally determined,
and since human beings are parts of the world, they are too. Many took
this to be strongly confirmed by the spectacular success of Isaac
Newton’s framework for understanding the universe as governed
everywhere by fairly simple, exceptionless laws of motion. But the
quantum revolution of the early twentieth century has made that
‘clockwork universe’ image at least doubtful at the level
of basic physics. While quantum mechanics has proven spectacularly
successful as a framework for making precise and accurate predictions
of certain observable phenomena, its implications for the causal
structure of reality is still not well understood, and there are
competing indeterministic and deterministic interpretations. See the
entry on
quantum mechanics
for detailed discussion.) It is possible that
indeterminacy on the small-scale, supposing it to be genuine,
‘cancels out’ at the macroscopic scale of birds and
buildings and people, so that behavior at this scale is virtually
deterministic. But this idea, once common, is now being challenged
empirically, even at the level of basic biology. Furthermore, the
social, biological, and medical sciences, too, are rife with merely
statistical generalizations. Plainly, the jury is out on all these
inter-theoretic questions. But that is just a way to say that current
science does not decisively support the idea that everything
we do is pre-determined by the past, and ultimately by the distant
past, wholly out of our control. For discussion, see Balaguer (2009),
Koch (2009), Roskies (2014), Ellis (2016).

Maybe, then, we are subject to myriad causal influences, but the sum
total of these influences doesn’t determine what we do, they
only make it more or less likely that we’ll do this or that. Now
some of the a priori no-free-will arguments above center on
nondeterministic theories according to which there are objective
antecedent probabilities associated with each possible choice
outcome. Why objective probabilities of this kind might present
special problems beyond those posed by the absence of determinism has
been insufficiently explored to date. (For brief discussion, see
Vicens 2016 and O’Connor 2016.) But one philosopher who argues
that there is reason to hold that our actions, if undetermined, are
governed by objective probabilities and that this fact calls into
question whether we act freely is Derk Pereboom (2001, ch. 3; 2014,
ch. 3). Pereboom notes that our best physical theories indicate that
statistical laws govern isolated, small-scale physical events, and he
infers from the thesis that human beings are wholly physically
composed that such statistical laws will also govern all the physical
components of human actions. Finally, Pereboom maintains that
agent-causal libertarianism offers the correct analysis of free
will. He then invites us to imagine that the antecedent probability of
some physical component of an action occurring is \(0.32\). If the action
is free while not violating the statistical law, then, in a scenario
with a large enough number of instances, this action would have to be
freely chosen close to \(32\) percent of the time. This leads to the
problem of “wild coincidences”:

if the occurrence of these physical components were settled by the
choices of agent-causes, then their actually being chosen close to 32
percent of the time would amount to a coincidence no less wild than
the coincidence of possible actions whose physical components have an
antecedent probability of about 0.99 being chosen, over large enough
number of instances, close to 99 percent of the time. The proposal
that agent-caused free choices do not diverge from what the
statistical laws predict for the physical components of our actions
would run so sharply counter to what we would expect as to make it
incredible. (2014, 67)

Clarke (2010) questions the implicit assumption that free agent-causal
choices should be expected not to conform to physical
statistical laws, while O’Connor (2009a) challenges the more
general assumption that freedom requires that agent-causal choices not
be governed by statistical laws of any kind, as they plausibly would
be if the relevant psychological states/powers are strongly emergent
from physical states of the human brain.

Pereboom’s empirical basis for free will skepticism is very
general. Others see support for free will skepticism from specific
findings and theories in the human sciences. They point to evidence
that we can be unconsciously influenced in the choices we make by a
range of factors, including ones that are not motivationally relevant;
that we can come to believe that we chose to initiate a behavior that
in fact was artificially induced; that people subject to certain
neurological disorders will sometimes engage in purposive behavior
while sincerely believing that they are not directing them. Finally, a
great deal of attention has been given to the work of neuroscientist
Benjamin Libet (2002). Libet conducted some simple experiments that
seemed to reveal the existence of ‘preparatory’ brain
activity shortly before a subject engages in an ostensibly spontaneous
action. (Libet interpreted this activity as the brain’s
‘deciding’ what to do before we are consciously settled on
a course of action.) Wegner (2001) surveys all of these findings (some
of which are due to his own work as a social psychologist) and argues
on their basis that the experience of conscious willing is ‘an
illusion’. For criticism of such arguments, see Mele (2009),
O’Connor (2009c), and Nahmias (2014).

While Pereboom and others point to these empirical considerations in
defense of free will skepticism, other philosophers see them as
reasons to favor a more modest free will agnosticism (Kearns 2015) or
to promote revisionism about the ‘folk idea of free will’
(Vargas 2013; Nichols 2015).

3.2 Arguments for the Reality of Free Will

If one is a compatibilist, then a case for the reality of free will
requires evidence for our being effective agents who for the most part
are aware of what we do and why we are doing it. If one is an
incompatibilist, then the case requires in addition evidence
for causal indeterminism, occurring in the right locations in the
process leading from deliberation to action. Many think that we
already have third-personal ‘neutral’ scientific evidence
for much of human behavior’s satisfying modest compatibilist
requirements, such as Fischer and Ravizza’s
reasons-responsiveness account. However, given the immaturity of
social science and the controversy over whether psychological states
‘reduce’ in some sense to underlying physical states (and
what this might entail for the reality of mental causation), this
claim is doubtful. A more promising case for our satisfying (at least)
compatibilist requirements on freedom is that effective agency
is presupposed by all scientific inquiry and so cannot
rationally be doubted (which fact is overlooked by some of the more
extreme ‘willusionists’ such as Wegner).

However, effective intervention in the world (in scientific practice
and elsewhere) does not (obviously) require that our behavior be
causally undetermined, so the ‘freedom is rationally
presupposed’ argument cannot be launched for such an
understanding of freedom. Instead, incompatibilists usually give one
of the following two bases for rational belief in freedom (both of
which can be given by compatibilists, too).

First, philosophers have long claimed that we have introspective
evidence of freedom in our experience of action, or perhaps of
consciously attended or deliberated action. Augustine and Scotus,
discussed earlier, are two examples among many. In recent years,
philosophers have been more carefully scrutinizing the experience of
agency and a debate has emerged concerning its contents, and in
particular whether it supports an indeterministic theory of human free
action. For discussion, see Deery et al. (2013), Guillon (2014), Horgan
(2015), and Bayne (2017).

Second, philosophers (e.g., Reid 1788 [1969], Swinburne 2013)
sometimes claim that our belief in the reality of free will is
epistemically basic, or reasonable without requiring independent
evidential support. Most philosophers hold that some beliefs have that
status, on pain of our having no justified beliefs whatever. It is
controversial, however, just which beliefs do because it is
controversial which criteria a belief must satisfy to qualify for that
privileged status. It is perhaps necessary that a basic belief be
‘instinctive’ (unreflectively held) for all or most human
beings; that it be embedded in regular experience; and that it be
central to our understanding of an important aspect of the world. Our
belief in free will seems to meet these criteria, but whether they are
sufficient will be debated. Other philosophers defend a variation on
this stance, maintaining instead that belief in the reality of moral
responsibility is epistemically basic, and that since moral
responsibility entails free will, or so it is claimed, we may
infer the reality of free will (see, e.g., van Inwagen 1983,
206–13).

4. Theological Wrinkles

A large portion of Western philosophical work on free will has been
written within an overarching theological framework, according to
which God is the ultimate source, sustainer, and end of all else. Some
of these thinkers draw the conclusion that God must be a sufficient,
wholly determining cause for everything that happens; all of them
suppose that every creaturely act necessarily depends on the
explanatorily prior, cooperative activity of God. It is also commonly
presumed by philosophical theists that human beings are free and
responsible (on pain of attributing evil in the world to God alone,
and so impugning His perfect goodness). Hence, those who believe that
God is omni-determining typically are compatibilists with respect to
freedom and (in this case) theological determinism. Edwards (1754
[1957]) is a good example. But those who suppose that God’s
sustaining activity (and special activity of conferring grace) is only
a necessary condition on the outcome of human free choices need to
tell a more subtle story, on which omnipotent God’s cooperative
activity can be (explanatorily) prior to a human choice and yet the
outcome of that choice be settled only by the choice itself. For
important medieval discussions—the apex of philosophical
reflection on theological concerns—see the relevant portions of
Al-Ghazali IP, Aquinas BW and Scotus QAM.
Three positions (given in order of logical strength) on God’s
activity vis-à-vis creaturely activity were variously defended
by thinkers of this area: mere conservationism, concurrentism, and
occasionalism. These positions turn on subtle distinctions, which have
recently been explored by Freddoso (1988), Kvanvig and McCann (1991),
Grant (2016), and Judisch (2016).

Many suppose that there is a challenge to human freedom stemming not
only from God’s perfect power but also from his perfect
knowledge. A standard argument for the incompatibility of free will
and causal determinism has a close theological analogue. Recall van
Inwagen’s influential formulation of the ‘Consequence
Argument’:

If determinism is true, then our acts are the consequences of the laws
of nature and events in the remote past. But it is not up to us what
went on before we were born, and neither is it up to us what the laws
of nature are. Therefore, the consequences of these things (including
our present acts) are not up to us. (van Inwagen 1983, 16)

And now consider an argument that turns on God’s comprehensive
and infallible knowledge of the future:

If infallible divine foreknowledge is true, then our acts are the
(logical) consequences of God’s beliefs in the remote past.
(Since God cannot get things wrong, his believing that
something will be so entails that it will be so.) But it is not up to
us what beliefs God had before we were born, and neither is it up to
us that God’s beliefs are necessarily true. Therefore, the
consequences of these things (including our present acts) are not up
to us.

An excellent discussion of these arguments in tandem and attempts to
point to relevant disanalogies between causal determinism and
infallible foreknowledge may be found in the introduction to Fischer
(1989). See also the entry on
foreknowledge and free will.

Another issue concerns how knowledge of God, the ultimate Good, would
impact human freedom. Many philosophical theologians, especially the
medieval Aristotelians, were drawn to the idea that human beings
cannot but will that which they take to be an unqualified good. (As
noted above, Duns Scotus is an exception to this consensus, as were
Ockham and Suarez subsequently, but their dissent is limited.) Hence,
if there is an afterlife, in which humans ‘see God face to
face,’ they will inevitably be drawn to Him. Following
Pascal, Murray (1993, 2002) argues that a good God would choose to
make His existence and character less than certain for human beings,
for the sake of preserving their freedom. (He will do so, the argument
goes, at least for a period of time in which human beings participate
in their own character formation.) If it is a good for human beings
that they freely choose to respond in love to God and to act in
obedience to His will, then God must maintain an ‘epistemic
distance’ from them lest they be overwhelmed by His goodness or
power and respond out of necessity, rather than freedom. (See also the
other essays in Howard-Snyder and Moser 2002.)

If it is true that God withholds our ability to be certain of his
existence for the sake of our freedom, then it is natural to conclude
that humans will lack freedom in heaven. And it is anyways common to
traditional Jewish, Christian, and Muslim theologies to maintain that
humans cannot sin in heaven. Even so, traditional Christian theology
at least maintains that human persons in heaven are free. What sort of
freedom is in view here, and how does it relate to mundane freedom?
Two good recent discussions of these questions are Pawl and Timpe
(2009) and Tamburro (2017).

Finally, there is the question of the freedom of God himself. Perfect
goodness is an essential, not acquired, attribute of God. God cannot
lie or be in any way immoral in His dealings with His creatures
(appearances notwithstanding). Unless we take the minority position on
which this is a trivial claim, since whatever God does
definitionally counts as good, this appears to be a
significant, inner constraint on God’s freedom. Did we not
contemplate immediately above that human freedom would be curtailed by
our having an unmistakable awareness of what is in fact the Good? And
yet is it not passing strange to suppose that God should be less than
perfectly free?

One suggested solution to this puzzle takes as its point of departure
the distinction noted in section 2.3 between the ability to do
otherwise and sourcehood, proposing that the core metaphysical feature
of freedom is being the ultimate source, or originator, of one’s
choices. For human beings or any created persons who owe their
existence to factors outside themselves, the only way their acts of
will could find their ultimate origin in themselves is for such acts
not to be determined by their character and circumstances. For if all
my willings were wholly determined, then if we were to trace my causal
history back far enough, we would ultimately arrive at external
factors that gave rise to me, with my particular genetic
dispositions. My motives at the time would not be
the ultimate source of my willings, only the
most proximate ones. Only by there being less than
deterministic connections between external influences and choices,
then, is it be possible for me to be an ultimate source of my
activity, concerning which I may truly say, “the buck stops
here.”

As is generally the case, things are different on this point in the
case of God. As Anselm observed, even if God's character absolutely
precludes His performing certain actions in certain contexts, this
will not imply that some external factor is in any way a partial
origin of His willings and refrainings from willing. Indeed, this
would not be so even if he were determined by character to
will everything which He wills. God’s nature owes its
existence to nothing. Thus, God would be the sole and ultimate source
of His will even if He couldn’t will otherwise.

Well, then, might God have willed otherwise in any respect?
The majority view in the history of philosophical theology is that He
indeed could have. He might have chosen not to create anything at all.
And given that He did create, He might have created any number of
alternatives to what we observe. But there have been noteworthy
thinkers who argued the contrary position, along with others who
clearly felt the pull of the contrary position even while resisting
it. The most famous such thinker is Leibniz (1710 [1985]), who argued
that God, being both perfectly good and perfectly powerful, cannot
fail to will the best possible world. Leibniz insisted that this is
consistent with saying that God is able to will otherwise, although
his defense of this last claim is notoriously difficult to make out
satisfactorily. Many read Leibniz, malgré lui, as one
whose basic commitments imply that God could not have willed other
than He does in any respect.

One might challenge Leibniz’s reasoning on this point by
questioning the assumption that there is a uniquely best possible
Creation (an option noted by Adams 1987, though he challenges instead
Leibniz’s conclusion based on it). One way this could be is if
there is no well-ordering of worlds: some pairs of worlds are
sufficiently different in kind that they are incommensurate with each
other (neither is better than the other, nor are they equal) and no
world is better than either of them. Another way this could be is if
there is no upper limit on goodness of worlds: for every possible
world God might have created, there are others (infinitely many, in
fact) which are better. If such is the case, one might argue, it is
reasonable for God to arbitrarily choose which world to create from
among those worlds exceeding some threshold value of overall
goodness.

However, William Rowe (2004) has countered that the thesis that there
is no upper limit on goodness of worlds has a very different
consequence: it shows that there could not be a morally perfect
Creator! For suppose our world has an on-balance moral value of \(n\)
and that God chose to create it despite being aware of possibilities
having values higher than \(n\) that He was able to create. It seems
we can now imagine a morally better Creator: one having the same
options who chooses to create a better world. For critical replies to
Rowe, see Almeida (2008, ch. 1), O’Connor (2008), and Kray
(2010).

Finally, Norman Kretzmann (1997, 220–25) has argued in the
context of Aquinas’s theological system that there is strong
pressure to say that God must have created something or other, though
it may well have been open to Him to create any of a number of
contingent orders. The reason is that there is no plausible account of
how an absolutely perfect God might have a resistible
motivation—one consideration among other, competing
considerations—for creating something rather than nothing. (It
obviously cannot have to do with any sort of utility, for example.)
The best general understanding of God’s being motivated to
create at all—one which in places Aquinas himself comes very
close to endorsing—is to see it as reflecting the fact that
God’s very being, which is goodness, necessarily diffuses
itself. Perfect goodness will naturally communicate itself outwardly;
God who is perfect goodness will naturally create, generating a
dependent reality that imperfectly reflects that goodness. Wainwright
(1996) discusses a somewhat similar line of thought in the Puritan
thinker Jonathan Edwards. Alexander Pruss (2016), however, raises
substantial grounds for doubt concerning this line of thought.

Bibliography

Adams, Robert, 1987. “Must God Create the Best?” in his
The Virtue of Faith and Other Essays in Philosophical
Theology, New York: Oxford University Press, 51–64.